Hot-air furnace



(No Model.)

HOTAIR FURNACE.

o. M-LBRID G-ES.

Patented Sept. 26, 1 893.

W/ TNE SSE S UNITED STATES PATENT OFFICE.

, CHRISTOPHER MARTIN BRIDGES, OF SEATTLE, \VASHINGTON.

HOT-AIR Fu RNAC E.

SPECIFICATION forming part of Letters Patent No. 505,697, datedSeptember 26, 1893. Application filed March 29, 1892. Serial No.426,932. (No model.)

To 00% whom it may concern.-

Be it known that I, CHRISTOPHER MARTIN BRIDGES, of Seattle, in thecounty of King and State of Washington, have invented a new and ImprovedHot-Air Furnace, of which the following is a full, clear, and exactdescription.

The object of the invention is to provide a new and improved hot airfurnace, which is simple and durable in construction, very effective inoperation, and arranged to quickly heat the incoming air and keep itpure.

The invention consists in certain parts and details and combinations ofthe same, as will be fully described hereinafter and then pointed'out inthe claims.

Reference is to be had to the accompanying drawings forming a part ofthis specification, in which similar letters of reference indicatecorresponding parts in both figures.

Figure 1 is a vertical section of the improvement; and Fig. 2 is atransverse section of the same on the line 2-2 of Fig. 1.

The improved hot air furnace is provided with the usual exterior shellA, made in sections fastened together in any suitable manner.

Within the base or bottom section of the shell A is arranged the firepot B, provided in its bottom with a suitable grate C, discharging intothe ash pit E, also arranged in the lower section of the shell, andprovided at the front of the shell with a door E, for convenientlyremoving the ash pan D, held in the said ash pit E.

The fire pot B is preferably constructed with an interior casing 13,made of cast iron, and on the outside of which is shrunk a sleeve B ofcast sheet steel. Thus, in case the cast iron casing B should break orcrack, the pieces are held in position by the steel sleeves B so that nogas can escape from the fire pot into the interior of the shell A.

On top of the fire pot B is supported the combustion chamber or fire boxF, provided at its front with an opening G, through which the fuel isintroduced into the fire box and the pot B. The outer end of the openingG is covered by the usual door G. The fire box or combustion chamber Fis provided, near its upper end, with a smoke flue H, leading to thechimney I, for carrying off the smoke and gases.

Within the fire box F is arranged the hot air casing J, having aninclined bottom ex tending upward from the rear to the front in linewith the opening G, so that the said inclined bottom directs the fuelintroduced through the opening G to the fire pot B. In the middle ofthis hot air casing J, and extending from the bottom upward, is arrangeda pipe F, in communication with the fire box F, as is plainlyillustrated in Fig. 1. The

lower rear end of the hot air casing J is connected with a pipe K,formed with a flaring mouthK,openinginto thedouble cone-shaped flange L,arranged on the air duct L, extending to the outside, to permit theouter air to pass through the duct into the pipe K, and from the latterinto the hot air casing J. The rear or inner end L of the duct L extendsinto the hot air compartment N, formed by the shell A, around theseveral parts located within the said shell as above described.

Through the fire box F and through the top and bottom extend the airflues N, connecting the lower part of the hot air compartment N with thedome 0, so that the cold air entering the said compartment circulatesaround the fire box F and also through the same by passing through thefines N which heat the air previous to passing into the dome O. Thelatter is formed with the usual outlet openings 0, connected with theflues P, leading to the several rooms of the building. Each fiue P ispreferably provided with a valve chamber P from which lead branch pipesand within which is a valve P mounted on a vertical shaft P, foralternately opening and closing the branch pipes. The upper end of thehot air casing J discharges into a dome R, located within the shell domeO and provided with outlets R, from which'extend nozzles Q, madecone-shaped, and extending a short distance into the fiues P. Now, itwill be seen, that the hot air passing upward from the hot air casing Jinto the dome It, passes through the said nozzles Q with considerableforce, and as the hot air issues through the contracted ends of the saidnozzles it creates considerable draft within the lines P, so that theair is caused to travel rapidly in the said lines and is quicklydischarged into the several rooms of the building. It is understood thatin the several fiues P, the air from the ICO compartment N and extremelyhot air from the hot air casingJ mix,but the hot air issuing through thenozzles Q imparts a greater velocity to the air coming from the dome Oof the compartment N.

Having thus described my invention, I claim as new and desire to secureby Letters Patent 1. In a hot air furnace, the combination with an outershell provided with outlet fines, and a combustion chamber within theshell and forming with the shell a hot air compartment, of a hot aircasing within the combustion chamber, a dome with which the hot aircasing communicates and provided with nozzles projecting into the saidoutlet fines, and cold air pipes for admitting air to the said hot aircompartment and casing, substantially as described.

2. In a hot air furnace, the combination with an outer shell providedwith outlet flues, a combustion chamber within the shell and formingwith the shell a hot air compartment and a cold air duct conducting airinto the said compartment, of a hot air casing within the combustionchamber, a dome above the hot air casing and communicating therewith,cone shaped nozzles leading from the dome and projecting into the saidoutlet flues, and a cold air pipe leading from the hot air easing intothe first named cold air duct, substantially as described.

3. In a hot air furnace the combination with an outer shell providedwith outlet flues, a combustion chamber within the shell and formingtherewith a hot air compartment, and a cold air duct for conducting airto the said compartment, of a hot air casing within the combustionchamber and having an inclined bottom, a pipe projecting into the casingand having an open lower end, a dome above the hot air casing andcommunicating therewith, cone shaped nozzles leading from the dome andprojecting into the said outlet fines, and a cold air duct leading fromthe hot air easing into the first named cold air duct, substantially asherein shown and described.

CHRISTOPHER MARTIN BRIDGES.

WVitnesses:

H. E. Soorr, I. P. NIHELL.

